The present invention relates to a method and an apparatus for operating a control unit for controlling operational sequences in a vehicle.
One special operating case in the context of a method and an apparatus for operating a control unit for controlling operational sequences in a vehicle is the modification and/or adaptation of data and/or programs which are accessed by the control functions. What may be used for this purpose is an application device that is equipped with additional hardware. This additional hardware may contain an external memory and an application interface. The built-in local control device to be applied must, for that purpose, be connected to the application device. For that purpose, the local control device is opened and a memory module of the local control device is removed. In place of that memory module, the application interface and an external memory are connected to the local control device. The control functions continue to be localized in the local control device.
German Patent Application No. 33 18 410 describes a method of this kind for modifying and optimizing data and program sequences for a programmed control device, in particular to control ignition, fuel injection, or transmission shifting operations in motor vehicles. In this context, a modifiable-content program and a data memory arrangement is connected in the place of the regular memory arrangement of the programmable control device, and is loaded with its data. This may be done because the regular memory arrangement can be removed, and a plug that connects the microprocessor of the programmable control device to the modifiable-content memory arrangement can be inserted into a socket that is thereby rendered unoccupied. To the memory arrangement is coupled a computer having an input keyboard, with which the data or the contents of the memory arrangement can be modified. The external computer ascertains the new or modified memory contents in real time, and cyclically pass those ascertained results to the memory arrangement, where they take the place of the previous data. The control device accesses these new data in accordance with its previous function. It is therefore possible to use the series-production control devices (i.e., the respective local control device) to test modifications and to introduce and optimize additional functions.
A further apparatus for data manipulation is described by German Patent No. 39 17 979, which describes an emulation device for a control device that has at least one microprocessor and one data/program read memory. Additionally provided in this context, once again, is a data manipulation device that has a write/read memory which is connected to the microprocessor of the control device. Also provided is an external operating device, which is connectable to a (preferably serial) interface and whose purpose is to modify data of the write/read memory. The data manipulation device arranged in the housing of the control device has a switchover apparatus for switching over read access to the write/read memory or to the data/program read memory, the write/read memory being connected via bus lines to the microprocessor. As a result, it is believed that the operating device can be of substantially simpler design as compared to conventional emulation systems, not least because the data modification can be accomplished partially by way of the control device computer, since the fixed and variable memories are contained in the control device that is to be applied. Two plug-in sockets are provided for this purpose. The data/program read memory is then moved from the first plug-in socket in the control device into the second plug-in socket in the data manipulation device. The second plug-in socket is accessible via a bus system. Into the now-unoccupied first plug-in socket is inserted the data manipulation device, which now contains not only the original data/program read memory but also the write/read memory, and which makes available an interface for the external operating device.
It has been found that the aforesaid existing art does not yield optimum results in every respect. For example, the built-in control device must be opened every time to operate the control device in the aforementioned operating instance. This may entail considerable effort, especially in the case of complexly installed production control devices. A hybrid device that is installed in the oil pan of a transmission, for example, is almost inaccessible for the aforesaid existing art. Mechanically connected control devices, such as, for example, a clutch adjuster, may also increase complexity. One reason for this is that in the existing art, the control functions may continue to be performed by the local control device. Since the additional hardware is introduced only temporarily into the local control device, the latter must have a more complex design than would be necessary based on its actual function. It is also believed that an optimized design in terms of the application is essentially prohibited because of the excessive effort, since each production device would need to be equipped accordingly.
An exemplary embodiment of a method and an apparatus of the present invention has the advantage of making possible the operation of even poorly accessible control units to control operational sequences in a vehicle. For that purpose, when operational sequences are initially error-free, performance of the control functions in the control unit is at least partially suppressed in reaction to at least one definable condition. As a result, the suppressed control functions can be displaced, for example, into a second control unit. Thus a second control unit, such as, for example, in the form of an application control device, can advantageously be interposed in the original connection interface of the first control unit. The first control unit, such as, for example, the local control device, can thus be used as an intelligent actuator. Of the original functionality of the control functions, measurement functions, and actuation functions, only the measurement functions and the actuation functions, for example, continue to be performed. The control functions are at least partially displaced into the second control unit (the application control device). As a result, the first control unit (the local control device) does not need to be removed or opened. Similarly, the software expressed in the measurement functions, actuation functions, and control functions of the first control unit does not need to be modified. When the control unit is operating, all that needs to be selected is whether operation is to occur in a normal mode or an application mode.
Advantageously, a control device almost identical in design to the first control unit (the local control device) can be used as the second control unit (i.e., as the application control device). It is believed that this should considerably reduce the development outlay.
In addition, however, the second control unit (the application control device) can be of more complex design with no need for this to be true of all first control units (local control devices). For example, an application interface for connecting an external device can be introduced into this second control unit, but this need not be done in the case of the local control device. As a result, the series-production devices should be simpler to construct as compared to other devices, and at the same time an application control device could be manufactured from the outset in a manner optimized to its purpose. Complex and cost-intensive subsequent redesign can thereby be avoided.
Suppression of the performance of control functions can be advantageous not only for the application, or for the modification and/or adaptation of data and/or programs that are accessed by the control functions, but also for other operating instances. For example, when the local control device is being used exclusively and when operational sequences are error-free, it is possible to interrupt additional functions that, for example, are not needed or not desired and that have no safety relevance. This can be done, with the aid of a terminal or any other input capability, by the vehicle occupants themselves or by a repair shop.